Balanced tamper



March 15, 1960 J. J. KADLEC BALANCED TAMPER Filed Feb. 28, 1958 INVENTOR.

United States Patent BALANCED TAMPER Joseph J. Kadlec, La Crescenta, Calif.

Application February 28, 1958, Serial No. 718,259

4 Claims. (CI. 94-48) Generally speaking, the present invention relates to a tamping and truing device for wet concrete mix and, more particularly, relates to such a device which is of a balanced construction having a front portion adapted to be positioned in front of an operators body and two rearwardly directed side portions adapted to be positioned on each side of the operators body, thus defining a recess of a size and shape such as to receive vertically therethrough the operators body in substantial vertical alignment with the center of gravity of the entire tamping and truing device. The improved balanced tamping and truing device of 'the present invention is also provided with controllably vertically adjustable .handle means extending upwardly into similar transversely spaced handengageable positions spaced rearwardly from the front portion of the frame and coincident with an imaginary vertical plane passing transversely through the center of gravity of the entire tamping and truing device and, thus, also extending across said recess and throughthe region in which the body of an operator of the device is positioned when the device is in use. Therefore, it will readily be seen that the balanced tamping and truing device of the present invention can be very conveniently carried by the two hands of an operator of the device in a position aligned with the center of gravity of the device, which will 40 render the device very much more easily handled than is the case with unbalancedprior art tamping and truing devices. This is a decided advantage since operator fatigue will be reduced to a minimum. Also, by reason of this balancing feature of the present invention, a larger tamping and truing'area is provided, and a tamping and truing operation can be conducted very much more rapidly than with prior art devices intended for similar purposes.

With the above points in mind, it is an object of the present invention to provide an improved balanced tamping and truing device for wet concrete mix of a structure such as to normally be in a balanced position when held in the two hands of an operator who is standing erect, thus greatly increasing the speed with which tamping and truing operations can be carried on, and greatly minimizing operator fatigue.

It is a further object of the present invention to provide apparatus of the character set forth in the preceding ob ject which is of exceedingly simple, lightweight, rigid, and virtually foolproof construction.

It is a further object of the present invention to provide apparatus of the character set forth in either or both of the preceding objects which is of conveniently assemblable and/or disassemblable construction to facilitate storage in small space volume and/or to facilitate easy shipment or transport of the apparatus.

Other and allied objects will be apparent to those skilled in the art after a careful perusal, examination, and study of the accompanying illustrations, the present specification, and the appended claims.

To facilitate understanding of the invention, reference "ice will be made to the hereinbelowdescribed drawing, in which: p Fig. l is a perspective view of one illustrative embodiment of the present invention;

Fig. 2 is a top plan view, partly broken away; a Fig. 3 is a sectional view taken in the direction of the arrows III-III in Fig. 2; and

alignment with the center of gravity of the entire tamping and truing device. In the particular embodiment of the present invention illustrated, the above-mentioned base frame is of hollow tubular open construction, of substantially U-shape in plan view, and defines the connected tubular periphery of a substantially rectangular transverse longitudinal front portion and, at opposite ends thereof, two similar integrally connected substantially rectangular and substantially parallel rearwardly directed longitudinal side portions. In the particular embodiment illustrated, the hollow tubular open base frame is indicated generally at 1 and the integral tubular periphery defining said frame is indicated by the reference numeral 2. In the specific embodiment illustrated, said rectangular transverse substantially longitudinal front portion is indicated generally by the reference character F and each of said substantially rectangular and substantially parallel rearwardly directed longitudinal side portions is generally indicated by the reference character S.

Also generally speaking, the present invention includes a horizontal flat perforate sheet of material fastened to the frame in substantially coextensive relationship thereto.

In the specific example illustrated, said horizontal flat perforate sheet is indicated at 3 and takes the form of a sheet of expanded metal having a plurality of similar vertical holesywhich, in the specific example illustrated,

are of substantially diamond shape, as indicated by .the'

reference numeral 4, and smaller than the average particle size of the gravel in a wet concrete mix which is to be tamped and trued. In the specific example illustrated, the perforate sheet 3 is of substantially the same plan ;view size and shape as the frame 1 and extends across the bottom of said frame 1 and is fastened thereto by a plurality of suitably threaded fastener means such as nut, bolt, and washer means, indicated generally at 5.

Also generally speaking, the present invention includes controllably vertically adjustable handle means effectively connected to the frame and extending upwardly therefrom into two similar transversely spaced hand-engage able positions spaced rearwardly from the front portion of said frame and coincident with an imaginary vertical plane passing transversely through the center of gravity of the entire tamping and truing device and extending transversely across said recess. In the specific example illustrated, said handle means comprises two transversely spaced individual handles indicated generally at 6, each being of substantially inverted U-shape effectively connected with respect to the frame 1 at each side of the front portion F and adjacent the rear of each side portion S and extending upwardly therefrom into the two similarly transversely spaced hand-engageable positions referred to hereinabove. In the specific example illustrated, each of the handles indicated generally at 6 com- Patented Mar. 15,1960

prises an upper U-shaped tubular portion .7 slidably i telescopically engaged in two upwardly open tubular 7 standard portions 8 and adapted to be vertically ad usted and maintained in any desired vertical position by means of a plurality of vertically spaced apertures 9 in the upper portion 7, correspondinghorizontal parallel apen' tures ill in the standard portions 8, and laterally insertiblo and removable locking pins 11 which may be inserted into any aligned sets of the apertures 9 and '16 for vertical adjustment of the eifect iveoverall height of each of the handles 6.

bolt extending through the tion to the portions of the frame 1 and/ or the various perforate sheet 3 in addistructural members and bracing members already de- The lower end of each of the four tubular standards 8 is removably telescopically mounted on four corresponding upwardly directed mounting posts 12 (which, in the specific example illustrated, are of tubular form) and.

each of which is welded on a structural member 13. The two front structural members 13 at the front corners of the frame fare fastened to the front tubular portion 2 of the frame 1 by said threaded fastening means 5, are

fastened to a transverse structural member 14 by said scribed, thereby rigidly fastening all of the same together.

.- This arrangement provides a firm, rigid structure adapted to effectively maintain the entire frame 1 and, in particular, the perforate sheet 3 in a substantially flat horizontal plane for effective tamping and truing use.

' It should also be noted that the construction of the present invention is such that the handles and upright standards and' supporting braces areconveniently assemblable or disassemblable with respect to the frame,

thus providing a structure adapted to be shipped or stored in the smallest possible space volume and yet which can be conveniently assembled for use-into the structure shown in the figures. e

Also generally speaking, the present invention may include splash-minimizing protective screen means superthreaded fastening means 5, and are fastened by said threaded fastening means 5 to a middle tubular-portion 2M 0f the frame 1. Each of the two rear structural members 13 adjacent the rear .of each sideportion S is fastened to inside and outside tubular portions 2 of said side portions S of the frame 1 by said fastening means ever the apparatus isjto be transported or stored in a minimum space volume, each of the locking pins 17 is, removedfrom'the aligned apertures and 16, and each of the handles 6 and standards 8 is removed from the corresponding four mounting posts 12. Each forward corner region of the frame 1 is provided with four bra e;

ing members 18, each of which is fastened at itsupper end to a vertically directed hollow tubular guide member 1? ,by'means of projections 20 carried by the periphery of said hollow tubular guide member 19 having threadedfastening means 21 extending therethrough and through I the upper ends of each of the bracing members.18. Two ofsaidbracing members 18 at each front corner of they frame l haveitheirlower ends connected to thestruo tural member 13landthe structural member. 14 m. said threaded fastening'means 5. The outside bracing m m ber 18 at each front corner of the frame 1 is connected by saidthreaded fastening means 5 to the outside tubular portion 2 of'the frame 1. The inside bracing member 18 at each of the frontcorners of the frame 1 has its lower end connected by said threaded fastening means 5 to a structural member 22 extendingacross the inside and outside parts of the tubular portions2 of the frame 1 immediately in front of the recess R. The lowerends of each of the two transversely disposed bracing members the transverse structural member 13 The third bracing t member 18 adjacent the rear of each side portion Sof the frame 1 has its lower end connectedby said threaded? fastening means 5 to the rearward partof said middle tubular portion 2M of the frame 1 which extends rear-r wardly along the middle of each side portion S of the frame 1. It should be noted that each of the threaded fastening means 5 fastening the various structural memhers 13, 14, and 22, and the various bracing, members 18 with respect to the frame 1 may eachpreferably, though 18 adjacent the rear of the side portions S of the frame 1"are connected by said threaded fastening means ,5 to

imposed above the perforate sheet.

In the particular example illustrated, this takes the form of a very fine aperture *screen- 24 which lies immediately above all of the tubular elements making up the framel and which is retained thereon iby the multiple fasteners 5.

It should be clearly, noted that the side portions S ex tend rearwardly from the frontportion F, as seen in plan view,-so as topr'ovide the recess R 'in which an operator ofthe device is intended to stand while manually grasping each of the U-shaped upper handle portions 7 at a location approximately atthe center thereof and coincident with an imaginary vertical plane passing trans-' verselythrough the center of gravity of the entire tamping and truing device and extending transversely across therecess vR. lnjother words, each of the side portions ""Sgcxtends 'rearwardly farcnoughto cause a vertical line f'fthrough the center of gravity of the entire device to be {positioned in-the recess R where the operator is intended to stand. This means that when the operator. grasps each ofthe upper handle portions 7 at about the center-thereof while said operator is standing .withhis .b'ody positioned vertically extending through the recess R,'=t he entiretamping andtruing device will be balanced. The operator may then, while maintaining the device in -balanced position, merely. bend his knees landloiwer his body in a substantially vertical position until the perforate'sheet'3 impinges on theupper wet, surface of a wet icohcrete mix, at which time thewater from the very gfin'jc cementinthe wet --concrete mix willpenetrate the .apenturest in-theperforate sheet 3, thus allowing the perforatetshectil to move downwardly into the wet conetc mix-until the perforate sheet} impinges on gravel in theconcrete mixhaving anaverage particle size greater than the holes 4 in theperforate sheet 3. Thus said oversize-gravel will be effectively tamped downwardly and tru'e'd below the "level of the water and fine cement in the .wetconcrete mix. Thus when the entire concrete mix hardens, after such a tamping and truing operation with the, device of the present invention, the upper surface of thehardene'd concrete' will consists primarily of theicoalescedismall particles, which provide a very smooth upper surface not interrupted by relatively largeiparticles.

f ifhe screen24-prevents-the water and 'firie particles which pass uertically through the perforate sheet, 3 during the,

-.tanjiping oer-truing operation fromsplashing upwardly in Numcrous modifications and:- ariation sfo f the present f nvention will occur -to thoseskilled in the-art .after a v j 'begjnpl ld d; and comprehended herein "as fully t as if speai undesirable manner. However -it* shou'ld behoted that therscreen 24--rnay lee-modified or dispensed with entirely in cer tain forms of the present-"invention.

carefulnstudy hereof. All such, properly within the basic spirit and scope of-ethe present invention 'arezintended to cifica ly Q bQQL illustrated:andzclaimed herein.

not necessarily, consist of a vertically directed threaded bolt, carrying a washer and a threadednut, e ch enact compositions, configurations, constuuctions, relative positionings, andt-coope rative. relationships .of the i snclts smas sa {R na at h zatsssm critical, and can be modified substantially within the spirit of the present invention.

Theembodiments of the present invention specifically described and illustrated herein are exemplary only, and are not intended to limit the scope of the present invention, which is to be interpreted in the light of the prior art and the appended claims only, with due consideration for the doctrine of equivalents.

I claim:

1. A balanced tamping and truing device for wet concrete mix, comprising: a base frame lying substantially entirely in a horizontal plane and including a transverse longitudinal front portion having at each end a similar rearwardly directed longitudinal side portion defining therebetween a recess of a size and shape such as to receive vertically therethrough the body of an operatorin substantially vertical alignment with the center of gravity of the entire tamping and truing device; a horizontal flat perforate sheet of material fastened to said frame in substantially coextensive relationship thereto, said sheet having a plurality of vertical holes smaller than the average particle size of the gravel in a wet concrete mix which is to be tamped and trued; and a pair of vertically adjustable handle means secured to said frame at opposite sides of said recess, said handle means being substantially centered relative to an imaginary vertical plane passing transversely through the center of gravity of said tamper and transversely across said recess.

2. A balanced tamping and truing device for wet concrete mix, comprising: a hollow tubular open base frame lying substantially entirely in a horizontal plane and including a transverse longitudinal front portion having at opposite ends thereof two similar substantially parallel rearwardly directed longitudinal side portions defining therebetween a recess of a size and shape such as to receive vertically therethrough the body of an operator in substantially vertical alignment with the center of gravity of the entire tamping and truing device; a flat horizontal sheet of perforate material of substantially the same planview size and shape as said frame and fastened to and extending across the bottom of said frame, said sheet having a plurality of vertical holes smaller than the average particle size of the gravel in a wet concrete mix which is to be tamped and trued; and a pair of vertically adjustable handle means secured to said frame at opposite sides of said recess, said handle means being substantially centered relative to an imaginary vertical plane passing transversely through the center of gravity of said tamper and transversely across said recess.

3. A balanced tamping and truing device for wet concrete mix, comprising: a base frame lying substantially entirely in a horizontal plane, of substantially U-shape in plan view and defining the connected periphery of a V substantially rectangular transverse longitudinal front por- 1 tion and, at opposite ends thereof, two similar integrally connected substantially rectangular and substantially parallel rearwardly directed longitudinal side portions and defining therebetween a substantially rectangular recess of a size and shape such as to receive vertically therethrough the body of an operator in substantially vertical alignment with the center of gravity of the entire tamping and truing device; a fiat horizontal sheet of perforate ex panded metal of substantially the same plan-view size and shape as said frame and fas tened to and extending across the bottom of said frame, said sheet having a plurality of similar vertical holes smaller than the average particle size of the gravel in a wet concrete mix which is to be tamped and trued; and a pair of vertically adjustable handle means secured to said frame at opposite sides of said recess, said handle means being substantially centered relative to an imaginary vertical plane passing transversely through the center of gravity of said tamper and transversely across said recess.

4. A balanced tamping and truing device for wet concrete mix, comprising: a base frame lying substantially entirely in a horizontal plane, of substantially U-shape in plan view and defining the connected periphery of a substantially rectangular transverse longitudinal front portion and, at opposite ends thereof, two similar integrally connected substantially rectangular and substantially parallel rearwardly directed longitudinal side portions and defining therebetween a substantially rectangular recess of a size and shape such as to receive vertically therethrough the body of an operator in substantially vertical alignment with the center of gravity of'the entire tamping and truing device; a flat horizontal sheet of p erforate expanded metal of substanially the same plan-view size and shape as said frame and fastened to and extending across the bottom of said frame, said sheet having a plurality of similar vertical holes smaller than the average particle size of the gravel in a wet concrete mix which is to be tamped and trued; and a pair of vertically adjustable shaped handle means secured to said frame at opposite sides of said recess, said handle means being substantially centered relative to an imaginary vertical plane passing transversely through the center of gravity of said tamper and transversely across said recess.

References Cited in the file of this patent UNITED STATES PATENTS Rook Nev. 10, 1925 

